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I need help with system A. I have the other answer already

I need help with system A. I have the other answer already-example-1
User AlexanderRD
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\begin{gathered} \text{Add the two systems together} \\ x-3y=3 \\ -x-3y=3 \\ \\ \text{The }x\text{ cancels out leaving us with} \\ -6y=6 \\ \\ \text{Divide both sides by }-6 \\ \frac{\cancel{-6}y}{\cancel{-6}}=(6)/(-6) \\ y=-1 \end{gathered}

Substitute y = -1 to either one of the two systems


\begin{gathered} x-3y=3 \\ x-3(-1)=3 \\ x+3=3 \\ x=3-3 \\ x=0 \end{gathered}

Therefore, the solution (x,y) is ( 0 , -1 ).

User Rdurand
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